COMPASS MINERALS INTERNATIONAL INC

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

1. Accounting Policies and Basis of Presentation:

Compass Minerals International, Inc. (“CMI”), through its subsidiaries (collectively, the “Company”), is a leading global provider of essential minerals focused on safely delivering where and when it matters to help solve nature’s challenges for customers and communities. The Company’s salt products help keep roadways safe during winter weather and are used in numerous other consumer, industrial, chemical and agricultural applications. Its plant nutrition business is the leading North American producer of sulfate of potash (“SOP”), which is used in the production of specialty fertilizers for high-value crops and turf and helps improve the quality and yield of crops, while supporting sustainable agriculture. The Company’s principal products are salt, consisting of sodium chloride and magnesium chloride, and SOP. The Company is also working to develop long-term fire-retardant solutions to help combat wildfires. The Company’s production sites are located in the United States (“U.S.”), Canada and the United Kingdom (“U.K.”). The Company also provides records management services in the U.K. Except where otherwise noted, references to North America include only the continental U.S. and Canada, and references to the U.K. include only England, Scotland and Wales. References to “Compass Minerals,” “our,” “us” and “we” refer to CMI and its consolidated subsidiaries.

CMI is a holding company with no significant operations other than those of its wholly-owned subsidiaries. The consolidated financial statements include the accounts of CMI and its wholly-owned domestic and foreign subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.

The accompanying unaudited consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete consolidated financial statements. These unaudited consolidated financial statements should be read in conjunction with the consolidated financial statements of the Company for the annual period ended September 30, 2024, as filed with the Securities and Exchange Commission (the “SEC”) in its Annual Report on Form 10-K on December 16, 2024 (“2024 Form 10-K”). In the opinion of management, all adjustments, consisting of normal recurring adjustments considered necessary for a fair presentation, have been included.

The Company experiences a substantial amount of seasonality in its sales, including its salt deicing product sales. Consequently, Salt segment sales and operating income are generally higher in the first and second fiscal quarters (ending December 31 and March 31) and lower during the third and fourth fiscal quarters (ending June 30 and September 30). In particular, sales of highway and consumer deicing salt and magnesium chloride products vary based on the severity of the winter conditions in areas where the products are used. Following industry practice in North America and the U.K., the Company seeks to stockpile sufficient quantities of deicing salt throughout the first, third and fourth fiscal quarters (ending December 31, June 30 and September 30) to meet the estimated requirements for the winter season. Production of deicing salt can also vary based on the severity or mildness of the preceding winter season. Due to the seasonal nature of the deicing product lines, operating results for the interim periods are not necessarily indicative of the results that may be expected for the full fiscal year. The Company’s plant nutrition business is also seasonal. As a result, the Company and its customers generally build inventories during the plant nutrition business’ low demand periods of the year (which are typically winter and summer, but can vary due to weather and other factors) to ensure timely product availability during the peak sales seasons (which are typically spring and autumn, but can also vary due to weather and other factors). Lastly, any expected results of the Company’s fire retardant business are also seasonal with peak demand for fire retardant products and services occurring from June through September. The Company does not yet have a contract for fiscal 2025.

Significant Accounting Policies

The Company’s significant accounting policies are detailed in “Note 2 – Summary of Significant Accounting Policies” within Part II, Item 8 of its 2024 Form 10-K. There were no material changes in the Company’s significant accounting policies from those described in its 2024 Form 10-K.

Recent Accounting Pronouncements

In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures”, which updates reportable segment disclosure requirements primarily to include enhanced disclosures about significant segment expenses. The amendments are effective for fiscal years beginning after December 15, 2023, and for interim periods within fiscal years

beginning after December 15, 2024. Early adoption is permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statements. Management is currently evaluating this ASU to determine its impact on the Company's disclosures.

In December 2023, the FASB issued ASU 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures”, which updates income tax disclosures by requiring consistent categories and additional disaggregation of information in the rate reconciliation and income taxes paid by jurisdiction. The amendments are effective for fiscal years beginning after December 15, 2024. Early adoption is permitted. The amendments should be applied prospectively; however, retrospective application is permitted. Management is currently evaluating this ASU to determine its impact on the Company’s disclosures.

In November 2024, the FASB issued amended guidance related to disclosure of disaggregated expenses (“ASU 2024-03”). This amendment requires public business entities to provide detailed disclosures in the notes to financial statements disaggregating specific expense categories, including employee compensation, depreciation, and intangible asset amortization, as well as certain other disclosures to provide enhanced transparency into the nature and function of expenses. This new guidance is effective for annual periods beginning in the Company’s fiscal 2028 and interim periods following annual adoption, with early adoption permitted. This guidance will be applied on a prospective basis with retrospective application permitted. Management is currently evaluating this ASU to determine its impact on the Company’s disclosures.

2. Revenues:

Deferred Revenue

Deferred revenue represents collections under non-cancellable contracts before the related product or service is transferred to the customer. The portion of deferred revenue that is anticipated to be recognized as revenue during the succeeding twelve-month period is recorded in accrued expenses and other current liabilities on the Consolidated Balance Sheets. Deferred revenue as of both December 31, 2024 and September 30, 2024 was approximately $3.6 million.

See Note 9 for a disaggregation of sales by segment, type and geographical region.

3. Inventories:

Inventories consist of the following (in millions):

(a)Excludes certain raw materials and supplies of $41.1 million and $42.2 million as of December 31, 2024 and September 30, 2024, respectively, that are not expected to be consumed within the next twelve months, included in Other noncurrent assets in the Consolidated Balance Sheets.

4. Property, Plant and Equipment, Net:

Property, plant and equipment, net, consists of the following (in millions):

5. Goodwill and Intangible Assets:

Changes in the carrying amount of goodwill are summarized as follows (in millions):

6. Income Taxes:

The Company’s effective income tax rate differs from the U.S. statutory federal income tax rate primarily due to U.S. statutory depletion, state income taxes (net of federal tax benefit), nondeductible executive compensation over $1 million, foreign income, mining and withholding taxes, base erosion and anti-abuse tax, and valuation allowances recorded on deferred tax assets.

The effective tax rates applied to the three months ended December 31, 2024 were determined by excluding the U.S. losses from the overall estimated annual effective tax rate computations and a separate estimated annual effective tax rate was computed and applied to the ordinary U.S. losses.

Management assesses the available positive and negative evidence to estimate whether sufficient future taxable income will be generated to permit use of the existing deferred tax assets. A significant piece of objective negative evidence evaluated was the cumulative loss incurred in the U.S. over the three-year period ended December 31, 2024. Such objective evidence limits the ability to consider other subjective evidence, such as the Company’s projections for future income. On the basis of this evaluation, during the three months ended December 31, 2024, an additional valuation allowance of $9.5 million has been recorded to recognize only the portion of the U.S. deferred tax assets that is more likely than not to be realized. The amount of the deferred tax assets considered realizable, however, could be adjusted if objective negative evidence in the form of cumulative losses is no longer present and additional weight is given to subjective evidence such as the Company’s projections for income.

As of December 31, 2024 and September 30, 2024, the Company had $78.4 million and $76.4 million, respectively of gross federal NOL carryforwards that have no expiration date and $6.6 million and $6.1 million at December 31, 2024 and September 30, 2024, respectively of net operating tax-effected state NOL carryforwards which expire beginning in 2031.

Canadian provincial tax authorities have challenged tax positions claimed by one of the Company’s Canadian subsidiaries and have issued tax reassessments for fiscal years 2002-2019. The reassessments are a result of ongoing audits and total $192.8 million, including interest, through December 31, 2024. The Company disputes these reassessments and will continue to work with the appropriate authorities in Canada to resolve the dispute. There is a reasonable possibility that the ultimate resolution of this dispute, and any related disputes for other open tax years, may be materially higher or lower than the amounts the Company has reserved for such disputes. In connection with this dispute, local regulations require the Company to post security with the tax authority until the dispute is resolved. The Company has posted collateral in the form of a $152.3 million performance bond

and has paid $34.6 million to the Canadian tax authorities (most of which is recorded in other assets in the Consolidated Balance Sheets at December 31, 2024, and September 30, 2024), which is necessary to proceed with future appeals or litigation.

The Company expects that it will be required by local regulations to provide security for additional interest on the above unresolved disputed amounts and for any future reassessments issued by these Canadian tax authorities in the form of cash, letters of credit, performance bonds, asset liens or other arrangements agreeable with the tax authorities until the disputes are resolved.

The Company expects that the ultimate outcome of these matters will not have a material impact on its results of operations or financial condition. However, the Company can provide no assurance as to the ultimate outcome of these matters, and the impact could be material if they are not resolved in the Company’s favor. As of December 31, 2024, the Company believes it has adequately reserved for these reassessments.

Additionally, the Company has other uncertain tax positions as well as assessments and disputed positions with taxing authorities in its various jurisdictions, which are consistent with those matters disclosed in the Company’s 2024 Form 10-K.

7. Long-Term Debt:

Long-term debt consists of the following (in millions):

On December 12, 2024, the Company entered into an amendment to its 2023 Credit Agreement, which, among other things, eased the restrictions of certain covenants contained in the agreement. The amendment included increasing the maximum allowed consolidated total net leverage ratio (as defined and calculated under the terms of the amended 2023 Credit Agreement) to 6.5 x as of the last day of any quarter through the fiscal quarter ended September 30, 2025, then gradually stepping down to 4.50 x for the fiscal quarter ended December 31, 2026 and thereafter. The amendment also decreased the Revolving Commitments (as defined in the Existing Credit Agreement) from $375 million to $325 million with additional reductions stepping down to $250 million on July 1, 2026. In connection with this amendment, the Company paid fees totaling $2.0 million which were capitalized as deferred financing costs. Additional arrangement and legal fees of $1.0 million were expensed as of December 31, 2024.

As of December 31, 2024, the term loan and revolving credit facility under the 2023 Credit Agreement were secured by substantially all existing and future U.S. assets of the Company, the Goderich mine in Ontario, Canada and capital stock of certain subsidiaries. As of December 31, 2024 and September 30, 2024, the weighted average interest rate on all borrowings outstanding under the 2023 Credit Agreement was approximately 7.3% and 7.7%, respectively. Depending on the type, borrowings under the 2023 Credit Agreement accrue interest at a rate per annum equal to the Adjusted Term SOFR Rate, the Adjusted EURIBO Rate, Prime Rate or the CDO Rate (as defined in the credit agreement), as applicable, plus Applicable Margins (as defined in the credit agreement) which resulted in interest rates between 7.2% and 7.6% as of December 31, 2024, and 7.3% and 9.5% as of September 30, 2024.

Outstanding letters of credit totaling $14.9 million as of December 31, 2024 further reduced available borrowing capacity under the Company’s $325 million revolving credit facility to $80.5 million. The 2023 Credit Agreement requires the Company to maintain certain financial ratios, including a minimum interest coverage ratio and a maximum total net leverage ratio. The Company was in compliance as of December 31, 2024 with its debt covenants under the 2023 Credit Agreement and its AR Securitization Facility. The consolidated total net leverage ratio represents the ratio of (a) consolidated total net debt to (b)

consolidated adjusted earnings before interest, taxes, depreciation and amortization. Consolidated total net debt includes the aggregate principal amount of total debt, net of unrestricted cash not to exceed $75.0 million.